Wire and tape driving means



5 R. J. TINKHAM 12,499,699

WIRE AND TAPE DRIYING IEANS mm m. a, 51947 2 Sheet 7.

a 3 1 a 4 32 lnoentor RUSSELL a. iNKHAM,

ttomg Muph 7 1950 R; J. mum 2,499,699

WIRE Aim TAPE mum; MEANS mm mm a, 1947 I RUSSELL J. TINKHAM,

' (women Patented Mar. 7, 1950 wnm AND TAPE DRIVING mans Russell J. Tinkham, Chicago, IlL, alsignor to Magnecord, Inc., Chicago, Ill., a corporation of Illinois Application Juno 6, 1947, Serial No. 753,125

12 Claims. (Cl. 271-211) This invention relates to improvements in wire and tape driving means, and more particularly to an improved means for positively driving fine wires, thin tapes, and like media devoid of the usual sprocket teeth holes at a constant linear speed. While designed for and especially applicable as a drive for the wire and tape record members of magnetic sound recorders, it will be understood that the driving means according to this invention is suitable for a variety of other uses wherein a smooth, positive drive of wires and tapes devoid of the conventional sprocket holes is required, as in the wire drawing and paper making industries.

Among the principal objects of the present inv'ention may be noted the provision of an improved and highly effective yet simplified driving means for positively driving fine wires, thin tapes and like media smoothly and at a constant linear speed; the provision of a wire and tape driving means which is capable of driving fine wires, thin tapes and like media without slippage; the provision of a wire and tape driving means which is effective to drive fine wires, thin tapes and like media smoothly and at a constant linear speed, regardless of the retarding or take-up tension existing in the wire or tape spooling systems usually associated therewith; and the provision of a wire and tape driving means which is characterized by inexpensive yet durable construction and by thoroughly dependable operation.

The above and other objects and advantages of the improved wire and tape driving means of the invention will be apparent from the following detailed description taken with the accompanying drawings illustrating a preferred physical embodiment thereof selected for the purpose of simple disclosure, and in which Fig. 1 is a side elevation of the roller system I employed in a wire and tape driving means according to the invention;

Fig. 2 is a section taken along line 2-2 of Fig. 1 illustrating the roller mounting Fig. 3 is a side elevation corresponding to Fig. 1 but illustrating the roller system opened up to facilitate loading of the wire or tape; and

Fig. 4 is a perspective view further illustrating the mounting of the driving rollers, and in particular the swing mounting of the upper pressure roller.

Referring to the drawings wherein like reference characters designate like parts throughout the several views, the wire and tape driving means of this invention is illustratively shown to be mounted from spaced upright members III, II of 65 a supporting frame which may be the frame structure of a magnetic sound recorder, for example. The wire or tape to be driven is represented by the numeral l2 and, in connection with the showing'of tape in'Fig. 2, such is to be regarded as illustrative only, as the herein driving means is capable of driving a variety of wireand tape-form media devoid of the usual sprocket teeth holes.

According to the invention, a smooth, positive drive is imparted to the wire or tape I! by the action thereon of a system of rollers l3, l4 and I5, of which the roller I3 is powered by a suitable means, roller H is driven by pressure contact with the powered roller l3, and roller I5 is driven by pressure contact with roller II. The roller I3 is hard-surfaced and usually metallic, although any durable material capable of giving a smooth, hard surface may be employed. Preferably, rollers l4 and I5 have resilient, high friction surfaces such as provided by rubber, synthetic rubber, cork and like material having the requisite resiliency as to embed the wire or tape being fed when the rollers are in feeding relationship, and a high coefficient of friction when in engagement with a smooth, hard surfaced roller such as the roller l3. The latter rollers may be formed of solid stock or they may consist of metallic cores surfaced with a resilient covering bonded to the core periphery in a manner well known in the art. As best seen in Fig. 2, the width of the surfaces of rollers l4, l5 substantially exceeds the width of the tape I 2 (or wire) being fed, so that when the rollers are in driving relationship, roller l4 maintains pressure contact with the powered driving roller [3 and roller l5 similarly maintains pressure contact with roller I4, the tape or wire being fed meanwhile embedding itself in the resilient surfaces of the rollers I4, 15.

By reference to Figs. 2 and 4, roller I3 is carried at the forward end of a shaft i6 journaled for rotation in spaced bearings I'I, i'la mounted in the upright support members l0 and H generally as shown, the shaft having its rearward end formed as a drive fitting Ilia adapted to be coupled to a motor or the like (not shown) which supplies power to the drive system. Pressure roller I4 is mounted for free rotation on the forward end of a shaft l8 which projects forwardly through a slot I9 provided in the front support member Ill. Shaft I8 is fixed at its rearward end to the outer end of an arm 20 carried by a rock shaft 22 which extends between the upright support members l0 and H and is journaled for 3 rotation in bearings mounted in said members. Suitable lever means to hold roller l4 either in contact with or out of contact with the powered rollerit are provided, such illustratively comprising an arm 23 carried at the rearward end.

of the rock shaft 32 and being angularl offset from arm 20 in clockwise direction. The offset lever arm 23 is connected by 'a tension spring 24 to a fixed point on the frame such as provided by a pin 23 carried by the rear support member I I. It will be observed that the lever arms 20. 23 and rock shaft 22 function as a double-arm bellcrank assembly through which tension spring 24 acts normally to hold the first pressure roller l4 in pressure contact with the roller l3. The tension of spring 24 is sufiiciently great as to bend the wire or tape l2 feeding between the rollers I4, I 3 around the latter roller, as seen in Fig. 1. As also seen in this figure, the normal linear position assumed by the spring 24 is to the left side of the axis of rock shaft 22, the substantially upright position of the rear bellcrank arm 23 insuring and fixing such normal positioning of the spring.

The described mounting of the pressure roller l4 permits its movement to a raised or disengaged position, the shaft l8 meanwhile moving along the slot l3. Consequent to such movement, bellcrank arm 23 moves clockwise to an inclined position as shown in Fig. 3, with spring 24 moving past center with respect to the axis of rock shaft 22, and thereupon functioning to hold the roller [4 in raised position as is desirable to permit loading of a wire or tape I! to be driven.

The second pressure roller 15 aforesaid is mounted to rotate freely on a stud or shaft 28 carried at the end of an arm 29 pivoted as at 30 to the support member l so as to operate forwardly thereof. A tension spring 3| has its one end anchored to the free endof the arm 29 and its other end to a fixed point 32 on the support member. By reference to Fig. 1, it will be observed that spring 3| functions normally to maintain roller I in pressure contact with roller l4, when the latter is in its engaged or active position. Suitable means for preventing overtravel of the roller l5, upon the first pressure roller l4 being raised out of contact with the roller 1 3, may take the form of a stop pin 33 positioned generally as shown. Accordingly, the arrangement is such that, when roller [4 is raised to its inactive or disengaged position, the pressure normally effective on the roller system is released.

In a three-roller driving system such as described, the relative positioning and angular disposition of the centers or, more properly, the axes on which the rollers turn, are important. Referring to Fig. 1, it will be observed that in the driving or active position of the roller 14, its axis is disposed above and is angularly displaced forwardly of, or on'the downstream side of, the axis of roller l3, by an angle of approximately 60, although this angular displacement may be from 45-75. Moreover, the angle between the axes of rollers l3, l4 and the axes of roller I4 and rock shaft 22 is about 120, although said angle may vary between 90 and 140. By the aforesaid disposition of roller and shaft axes, a substantial increase in contact pressure between rollers l4 and I3 is achieved, as compared to a roller system in which the axes of rollers i3, i4 and shaft 22 are in line, for example, such increased contact pressure being due to the fact that the resistance of roller l4 to rotate when v g 4 driven by roller l3 tends to drive the roller l4- in downward direction as viewed in Fig. l with corresponding self-energizing eflect.

Similarly, the axis of roller II, which is disposed below the axis of roller i4, is angularly displaced forwardly 'of the axis of said roller [4 by an angle of approximately 15, although such angle may vary between 0 and 30". It ,will be also seen from Fig. 1 that the angle between the axes of arm pivot 30 and roller l5 and between the axes of rollers l3, I4 is preferably slightly in excess of 90, although suchangle may vary from 60 to.120, with the result that increased contact pressure between rollers l5, i4 is achieved. Moreover, by the aforesaid offsetting and angular disposition of roller axes, roller l4 causes the wire or tape being fed over the powered roller l3 to have a substantial angle of wrap thereon, which in the illustrated system is approximately 60. Similarly, the lower pressure roller l4 effects a substantial angle'of wrap of the wire or tape I 2 on the periphery of the pressure roller I 4 which, as shown, is about 90.

The aforesaid wrap angles taken with the pressure exerted on the wire or tape being fed through the roller system insures a positive, smooth drive and prevents slippage of the wire or tape, regardless of the varying tension imparted on either its supply or take-up side by the wire or tape spooling system which is usually associated with such a wire or tape driving means.

- Accordingly, by driving the powered shaft l3 at a constant angular velocity, the present driving means achieves in simple manner an effective drive for fine wires and thin tapes, especially useful in magnetic wire or tape recording systems, as well as in other systems in which positive, nonslip drive of like media devoid of the usual sprocket teeth holes is required.

Since the drawing illustrates only a single possible embodiment of a three-roller driving system, with substantial departure therefrom being permitted, depending on the particular application of such a system, it will be understood that the invention is not limited to the precise mechanism illustrated.

I claim:

1. Means for driving fine wires, thin tapes and like media comprising, in combination, a first powered roller, a second roller having pressure contact with said powered roller and being driven thereby, and a third roller having pressure contact with the second roller and being driven thereby, said first roller havin a smooth, hard surface and said second and third rollers each having a resilient, high friction surface in which the media being driven may embed itself when the rollers are in feeding relationship.

2. Means for driving fine wires, thin tapes and like media comprising, in combination, a first powered roller, second and third rollers each mounted for free rotation, said first roller having a smooth, hard surface and said second and third rollers each having a resilient, high friction surface in which the media being driven may embed itself when the rollers are in feeding relationship, means normally urging the second roller into pressure contact with the powered roller, and means normally urging said third roller into pressure contact with the second roller.

3. Means for driving fine wires, thin tapes and like media comprising, in combination, a first power-driven roller, a second roller having driving contact with the first roller and being mounted for free rotation about an axis which is disposed above and angularly displaced relatively forwardly of the axis of said first roller, and .a third roller having driving contact with the second roller and being mounted for free rotation about an axis which is disposed below that of the second roller, saidfirst roller having a smooth, hard surface and said second and third rollers each having a resilient, high friction surface in which the media being driven may embed itself when the rollers are in feeding relationship.

4. Means for driving fine wires, thin tapes and like media comprising, in combination, a first power-driven roller having a smooth, hard surface, second and third driven rollers each having a resilient, high friction surface in which the media being driven may embed itself when the rollers are in feeding relationship, said second roller having driving contact with the first roller and being mounted for free rotation about an axis which is disposed above and angularly displaced relatively forwardly of the axis of said first roller, and said third roller having driving contact with the second roller and being mounted for free rotation about an axis which is disposed below and angularly displaced relatively forwardly of the axis of the second roller.

5. Means for driving fine wires, thin tapes and like media comprising, in combination, a first power-driven roller having a smooth, hard sure face, second and third driven rollers each hav. ing a resilient, high friction surface in which the media being driven may embed itself when the rollers are in feeding relationship, said second roller having driving contact with the first roller and being mounted for free rotation about an axis which is disposed above and displaced angularly forwardly of the axis of the first roller by an angle of from 45-75, whereby to cause the media to have a corresponding angular wrap on the periphery of the first roller, and said third roller having driving engagement with said second roller and being mounted for free rotation about an axis which is disposed below and angularly displaced forwardly of the axis of the second roller by an angle of between 0-30.

6. Means for driving fine wires, thin tapes and like media comprising, in combination, a first power-driven roller having a smooth, hard surface, second and third driven rollers each having a resilient, high friction surface in which the media being driven may embed itself when the rollers are in feeding relationship, said second roller having driving contact with the first roller and being mounted for free rotation about an axis which is disposed above and displaced angularly forwardly of the axis of the first roller by an angle of approximately 60, whereby to cause the media to have a corresponding angular wrap on the periphery of the first roller, and said third roller having drivin engagement with said second roller and being mounted for free rotation about an axis which is disposed below and angularly displaced forwardly of the axis of the second roller by an angle of approximately '7. Means for driving fine wires, thin tapes and like media comprising, in combination, a powerdriven first roller having a smooth, hard surface, second and third driven rollers each having a resilient, high friction surface in which the media being driven may embed itself when the rollers are in feeding relationship, said second roller mounted for free rotation on the axis of a shaft carried at the end of an arm mounted for angular movement, resilient means operative through said arm for urging said second roller into driving contact with the first roller, said third roller mounted for free rotation on the axis of a shaft carried at the end of a second arm mounted for angular movement, and resilient means operative through said second arm for urging said third roller into driving contact with the second roller.

8. Means for driving fine wires, thin tapes and like media as set forth in claim 7, wherein the axis of rotation of the second roller is disposed above and angularly forwardly of the axis of the first roller by an angle of approximately 60, and wherein the axis of the third roller is disposed below and angularly forwardly of the axis of the second roller by an angle of approximately 30.

9. Means for driving fine wires, thin tapes and like media as set forth in claim 7, wherein the second roller is movable through angular movement of the first-named arm to an inactive position, and wherein said resilient means is operative through said arm to maintain the sec-, ond roller in said inactive position.

10. Means for driving fine wires, thin tapes and like media comprising, in combination, a powerdriven first roller having a smooth, hard surface, second and third driven rollers each having a resilient high friction surface in which said media being driven may embed itself when the rollers are in feeding relationship, means mounting said second roller for angular movement from an active position in which it has driving contact with the first roller to an inactive position in which it is clear thereof, spring means for maintaining said second roller in either of said positions to which it has been actuated, and spring means operative to maintain said third roller in driving'contact with the second roller when the latter is in its active position aforesaid.

11. Means for driving fine wires, thin tapes and like media comprising, in combination, a power driven first roller having a smooth, hard surface turning on a fixed axis, second and third driven rollers each having a resilient, high friction surface in which said media being driven may embed itself when the rollers are in feeding relationship, said second roller'being mounted for free rotation on the axis of a shaft carried at the end of an arm mounted for angular movement about a second fixed axis, resilient means operative through said arm for urging the second roller into driving contact with the first roller, the angle between the first fixed axis, the shaft axis and the second fixed axis being between and 140, said third roller being mounted for free rotation on the axis of a second shaft carried at the end of a second arm mounted for angular movement about a third fixed axis, and resilient means operative through said second arm for urging the third roller into driving contact with the second roller, the angle between the third fixed axis, the second shaft axis and the first shaft axis being between 60 and 12. Means for driving fine wires, thin tapes and the like media comprising, in combination, a power driven first roller having a smooth, hard surface turning on a fixed axis, second and third driven rollers each having a resilient, high friction surface in which said media being driven may embed itself when the rollers are in feeding relationship, said second roller being mount- 7 ed for tree rotation on the axis of a shaft carried at the end of an arm mounted for angular' between the third fixed axis, the second shaft 15 axiaandthefirstlhattaxisbdngapproximateiy 90.

RUSSELL J. 'I'INKEAM.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 10 Number Name Date 853,604 Smith May 14, 1907 1,623,052 Garrard Apr. 5, 1927 2,033,277 Elmer et al Mar. 10', 1936 2,181,318 Fessenden Nov. 28, 1939 2,398,355

Bristol Apr. 16, 1948 

